Fixative for perfume compositions

ABSTRACT

A fixative for perfume compositions, 1-(2,6,6-trimethylcyclohexyl)-hexane-3-ol, itself odorless to many people, brings about a &#34;rounding-off&#34; of the perfume while increasing its intensity. The compound is made by condensation of citral with pentane-2-on, followed by cyclization and hydration.

FIELD OF INVENTION

The present invention relates to the new compound 1-(2,6,6-trimethyl-cyclohexyl)-hexane-3-ol having the structural formula I, ##STR1## its manufacture, as well as its use as fixative for perfume compositions.

SUMMARY OF INVENTION

It has been found that an addition of 1-(2,6,6,-trimethyl-cyclohexyl)-hexane-3-ol effectively brings about a "rounding-off" and fixation of perfume compositions while simultaneously increasing the intensity of the fragrance. The quantity used amounts usually to 1 to 25% by weight relative to the total composition, and a very distinct fixing effect can be ascertained particularly from approximately 3%. In principle, more than 25% may also be employed; this depends, however, upon the nature of the total composition and may be easily determined by routine experiments. The term "perfume composition" is meant to here define a so-called perfume oil, in other words, the concentrate, which is then thinned to obtain a perfume, or which is used for scenting cosmetic products, for example, soaps, hair lotions or creams. Such a perfume oil contains, in addition to the fixative, odoriferous substances and volatile oils.

DETAILED DESCRIPTION OF EMBODIMENTS

The 1-(2,6,6-trimethylcyclohexyl)-hexane-3-ol itself is not to be considered as an odoriferous substance in the conventional sense as this saturated secondary alcohol has been found to be odorless, or only very slightly scented, by a significant number of the test persons who were asked to judge this substance, whereas other persons perceived an intensely radiating wood-like, slightly animalic-urinary odor.

Anosmia, i.e. the incapability to perceive smells, which numerous people have with respect to this new alcohol, may be compared with the effect of various very expensive animalic fixatives, such as musk and amber, whose scent can also be noticed only faintly by certain people, or not at all.

The occurrence of anosmia with respect to a specific substance, particularly in the area of perfumery, appears to always point out to particularly good fixative properties of a substance and holds true at least for all of the fixatives which have heretofore been employed in the manufacture of perfume compositions. These afore-mentioned advantageous properties of 1-(2,6,6-trimethylcyclohexyl)-hexane-3-ol distinguish this substance from the homologous products which have been known for a long time, such as iso-tetrahydromethylionol and n-tetrahydromethylionol, which do not develop any fixative effect and with regard to which also no cases of anosmia have been ascertained.

The product 1-(2,6,6-trimethylcyclohexyl)-hexane-3-ol may be obtained, analogous to the method disclosed in the Journal of the American Chemical Society 46, 119 (1924) and Helv. Chim. Acta 26, 2151 (1943), by condensation of citral with pentane-2-on in the presence of bases to 8,12-dimethyltrideca-5,7,11-tri-en-4-on, cyclization thereof with phosphoric acid, and subsequent total hydration of the cyclization product. For example, the condensation may be carried out in the presence of alkali hydroxide, such as NaOH or KOH, e.g. in an alcoholic solution, at about room temperature, in an inert solvent. The cyclization may be carried out by a slow addition of phosphoric acid at slightly below room temperature, a subsequent slight heating to room temperature while stirring for several hours, and renewed slight heating to approximately 10° C. above room temperature again while stirring for several hours. The hydration may suitably be carried out catalytically under pressure using, e.g. Raney nickel, and at a temperature rising to 150°-200° C.

The following examples show, on the one hand, the manufacture of the new compound 1-(2,6,6-trimethylcyclohexyl)-hexane-3-ol and, on the other hand, some formulations for the use of 1-(2,6,6-trimethylcyclohexyl)-hexane-3-ol as fixative in perfume oils.

EXAMPLE 1 Manufacture of 1(2,2,6-trimethylcyclohexyl)-hexane-3-ol

First Stage:

Dropped into 1,520 grams of citral and 1,720 grams of methyl-n-propyl ketone while stirring at a temperature of 20°-25° C., are 32 grams of sodium hydroxide dissolved in 200 ml methanol. The reaction medium is stirred at that temperature for 24 hours. Thereafter, neutralization is effected with 60 grams glacial acetic acid, the reaction water formed is separated, and the solvent as well as any excess of methyl-n-propyl ketone are distilled off. The reaction product is purified by distillation. The yield is 1.66 kilograms of 8,12-dimethyltrideca-5,7,12-tri-en-4-on.

Kp₂ (boiling point): 225° C., d₄ ²⁰ =0.9134; n_(D) ²⁰ =1.5232.

Second Stage:

1.66 kilograms of 8,12-dimethyltrideca-5,7,12-tri-en-4-on dissolved in 3 kilograms benzene are dropped while stirring at 10°-15° C. into 1.66 kilograms phosphoric acid and the reaction mixture is stirred for 2 hours at 20° C. and thereafter for 3 hours at 30° C. Thereupon water is added, the aqueous phase is extracted twice with benzene, the benzene extract is neutrally washed with sodium carbonate solution, and the benzene is then removed by distillation. The reaction product is purified by distillation. The yield is 1.3 kilograms 1-(2',6',6'-trimethylcyclohex-2'-enyl)-hex-1-en-3-on.

Kp₂ : 190° C., d₄ ²⁰ =0.9389; n_(D) ²⁰ =1.4953.

Third Stage:

1.3 kilograms of 1-(2',6',6'-trimethylcyclohex-2'-enyl)-hex-1-en-3-on are hydrated in the presence of Raney nickel as catalyst at 100 atmospheres excess H₂ pressure, until 3 mol H₂ have been absorbed. In the course of the hydration, the reaction temperature is increased to 180° C. The hydration product is purified by distillation. The yield is 1.1 kilogram 1-(2',6',6'-trimethylcyclohexyl)-hexane-3-ol.

Kp₂ : 123° C.; d₄ ²⁰ =0.9147; n_(D) ²⁰ =1.4720.

EXAMPLE 2 Rose Bouquet

    ______________________________________                                         300 grams  phenyl ethyl alcohol                                                200 grams  citronellol                                                         100 grams  geraniol                                                            100 grams  phenyl ethyl acetate                                                50 grams   aldehyde C 11 undecylene, 10% in DPG                                50 grams   geranium oil Bourbon                                                50 grams   trichloro phenyl ethyl acetate                                      40 grams   ionone beta                                                         30 grams   citronellyl acetate                                                 20 grams   aldehyde C 9, 10% in DPG                                            20 grams   iron beta, 10% in DPG                                                          4-methyl-2-isobutenyl tetrahydro pyrane in a                        10 grams   10% DPG solution                                                    970 grams                                                                      ______________________________________                                    

When 30 grams 1-(2,6,6-trimethylcyclohexyl)-hexane-3-ol are added to the above mixture, it provides to the mixture a radiating fragrance which is noticeable for a considerably longer period of time than the fragrance or aroma of the above mixture without such addition.

EXAMPLE 3 Perfume Oil with an Exotic, Flowery Aroma

    ______________________________________                                         140 grams                                                                               phenyl ethyl alcohol                                                  120 grams                                                                               alpha-hexyl-cinnamic aldehyde                                         100 grams                                                                               benzylacetate                                                         90 grams hydroxy-citronellal                                                   85 grams p-tert. butyl-α-methyl dihydrocinnamic aldehyde                 85 grams French lavender oil 4=/42%                                            65 grams nerol                                                                 40 grams cumarin                                                               40 grams musk ketone                                                           40 grams musk ambrette                                                         25 grams linalool                                                              20 grams amyl salicylate                                                       20 grams eugenol                                                               20 grams ylang-ylang oil extra                                                 15 grams patchouli oil Singapore                                               10 grams vanillin                                                              5 grams  iron beta                                                             920 grams                                                                      ______________________________________                                    

An addition of 100 grams 1-(2,6,6-trimethylcyclohexyl)-hexane-3-ol intensifies the flowery aroma and imparts to the perfume a considerably longer adherence.

EXAMPLE 4 Perfume Oil with a Wood-Like-Powdery Aroma for Soaps

    ______________________________________                                         150 grams      benzyl benzoate                                                 100 grams      cumarin                                                         100 grams      geraniol                                                        100 grams      lavandin abrialis                                               100 grams      linalyl acetate                                                 75 grams       phenyl ethyl alcohol                                            65 grams       patchouli oil Sing. rect.                                       50 grams       linalool                                                        35 grams       geranium oil Bourbon                                            20 grams       alpha-hexyl-cinnamic aldehyde                                   20 grams       East Indian sandalwood oil                                      5 grams        anisealdehyde                                                   2 grams        aldehyde C 12 laurin                                            822 grams                                                                      ______________________________________                                    

An addition of 228 grams 1-(2,6,6-trimethylcyclohexyl)-hexane-3-ol imparts to the previously somewhat dull and flat-smelling perfume composition a long-lasting, radiant and natural fragrance.

It will be obvious to those skilled in the art that various changes may be made without departing from the scope of the invention and the invention is not to be considered limited to what is described in the specification. 

What is claimed is:
 1. 1-(2,6,6-trimethylcyclohexyl)-hexane-3-ol. 